RT Journal Article SR Electronic T1 Extending screening mammography to include younger women minimally increased life expectancy with large increases in cost JF Evidence Based Medicine JO Evid Based Med FD BMJ Publishing Group Ltd SP 95 OP 95 DO 10.1136/ebm.1998.3.95 VO 3 IS 3 YR 1998 UL http://ebm.bmj.com/content/3/3/95.abstract AB